Commit cc34f290 authored by Max Filippov's avatar Max Filippov
Browse files

xtensa: rearrange show_stack output 



Minimal stack alignment on xtensa is 16 bytes, having stack dump in
32-byte lines may be visually misleading as the stack frame border may
be in the middle of the line.
Arrange stack dump in 16-byte lines. Mark lines at stack frame borders
with arrows.

Signed-off-by: default avatarMax Filippov <jcmvbkbc@gmail.com>
parent f29cf776

arch/xtensa/kernel/traps.c

+42 −15
Original line number Diff line number Diff line
@@ -549,31 +549,58 @@ static void show_trace(struct task_struct *task, unsigned long *sp, 
}



#define STACK_DUMP_ENTRY_SIZE 4

#define STACK_DUMP_LINE_SIZE 32

#define STACK_DUMP_LINE_SIZE 16

static size_t kstack_depth_to_print = CONFIG_PRINT_STACK_DEPTH;



struct stack_fragment

{

	size_t len;

	size_t off;

	u8 *sp;

	const char *loglvl;

};



static int show_stack_fragment_cb(struct stackframe *frame, void *data)

{

	struct stack_fragment *sf = data;



	while (sf->off < sf->len) {

		u8 line[STACK_DUMP_LINE_SIZE];

		size_t line_len = sf->len - sf->off > STACK_DUMP_LINE_SIZE ?

			STACK_DUMP_LINE_SIZE : sf->len - sf->off;

		bool arrow = sf->off == 0;



		if (frame && frame->sp == (unsigned long)(sf->sp + sf->off))

			arrow = true;



		__memcpy(line, sf->sp + sf->off, line_len);

		print_hex_dump(sf->loglvl, arrow ? "> " : "  ", DUMP_PREFIX_NONE,

			       STACK_DUMP_LINE_SIZE, STACK_DUMP_ENTRY_SIZE,

			       line, line_len, false);

		sf->off += STACK_DUMP_LINE_SIZE;

		if (arrow)

			return 0;

	}

	return 1;

}



void show_stack(struct task_struct *task, unsigned long *sp, const char *loglvl)

{

	size_t len, off = 0;

	struct stack_fragment sf;



	if (!sp)

		sp = stack_pointer(task);



	len = min((-(size_t)sp) & (THREAD_SIZE - STACK_DUMP_ENTRY_SIZE),

	sf.len = min((-(size_t)sp) & (THREAD_SIZE - STACK_DUMP_ENTRY_SIZE),

		     kstack_depth_to_print * STACK_DUMP_ENTRY_SIZE);

	sf.off = 0;

	sf.sp = (u8 *)sp;

	sf.loglvl = loglvl;



	printk("%sStack:\n", loglvl);

	while (off < len) {

		u8 line[STACK_DUMP_LINE_SIZE];

		size_t line_len = len - off > STACK_DUMP_LINE_SIZE ?

			STACK_DUMP_LINE_SIZE : len - off;



		__memcpy(line, (u8 *)sp + off, line_len);

		print_hex_dump(loglvl, " ", DUMP_PREFIX_NONE,

			       STACK_DUMP_LINE_SIZE, STACK_DUMP_ENTRY_SIZE,

			       line, line_len, false);

		off += STACK_DUMP_LINE_SIZE;

	}

	walk_stackframe(sp, show_stack_fragment_cb, &sf);

	while (sf.off < sf.len)

		show_stack_fragment_cb(NULL, &sf);

	show_trace(task, sp, loglvl);

}